US 20080178029 A1
Aspects of the subject matter described herein relate to using priorities to select power usage for multiple devices. In aspects, workloads or the devices to which they are assigned are each assigned a priority. To remain within a power budget, the power levels on one or more of the devices may be adjusted based on the priority assigned to the device (or a workload thereon). If needed, devices may be instructed to operate at lower power than associated with their priority or may even be shut down to remain within the budget. A data structure is used to associate workloads or devices with priorities.
1. A computer-readable medium having computer-executable instructions, which when executed perform actions, comprising:
obtaining a power budget for a plurality of workloads, the workloads being assigned to devices, the power budget indicating a maximum power that the devices together are allowed to consume;
obtaining a priority for a workload;
based at least in part on the priority, selecting a power profile for a device assigned to the workload; and
instructing the device to operate at a power level associated with the power profile.
2. The computer-readable medium of
3. The computer-readable medium of
4. The computer-readable medium of
5. The computer-readable medium of
6. The computer-readable medium of
7. The computer-readable medium of
8. The computer-readable medium of
obtaining a priority of another workload;
based at least part on the priority of the other workload, selecting a power profile for a device assigned to the other workload; and
instructing the device assigned to the other workload to operate at a power level associated with the power profile for the device assigned to the other workload.
9. The computer-readable medium of
10. The computer-readable medium of
11. The computer-readable medium of
12. A method implemented at least in part by a computer, the method comprising:
obtaining a power budget for a plurality of devices, the devices being associated with priorities, each device being associated with a power priority;
determining whether the power budget is greater than the power consumed by the devices when operating at full power;
if the power budget is greater than the power consumed by the devices when each device is operating at full power, determining whether to allow the devices to operate at full power; and
if the power budget is not greater than the power consumed by the devices when each device is operating at full power, instructing at least one of the devices to operate at a power level less than full power based at least in part on the power priority associated with the device.
13. The method of
14. The method of
15. The method of
16. The method of
17. A computer-readable medium having stored thereon a data structure, comprising:
a plurality of first fields for storing priorities of a plurality of devices assigned to workloads that are allotted a power budget over which a combined power draw of the devices is not to exceed, each power level indicating a maximum power a devices assigned to a workload is not to exceed at the power level; and
a plurality of second fields for storing associations between the power profiles and priorities, each priority being associated with at least one of the power profiles
18. The computer-readable medium of
19. The computer-readable medium of
20. The computer-readable medium of
A data center may include racks of servers, networking equipment, and other electronic devices. To determine how many devices a data center may handle, a power rating value of the power supply unit of each device may be used. This value is referred to as ‘label power’ and is typically much higher than the maximum power the particular device could ever draw. Using the ‘label power’ results in budgeting too much power for each device, and, as a result, servers may be populated more sparsely than they need to be. Data center floor space is very expensive and this under-utilization has a negative effect on the total cost of ownership for the data center.
Briefly, aspects of the subject matter described herein relate to using priorities to select power usage for multiple devices. In aspects, workloads or the devices to which they are assigned are each assigned a priority. To remain within a power budget, the power levels on one or more of the devices may be adjusted based on the priority assigned to the device (or a workload thereon). If needed, devices may be instructed to operate at lower power than associated with their priority or may even be shut down to remain within the budget. A data structure is used to associate workloads or devices with priorities.
This Summary is provided to briefly identify some aspects of the subject matter that is further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
The phrase “subject matter described herein” refers to subject matter described in the Detailed Description unless the context clearly indicates otherwise. The term “aspects” should be read as “at least one aspect.” Identifying aspects of the subject matter described in the Detailed Description is not intended to identify key or essential features of the claimed subject matter.
The aspects described above and other aspects of the subject matter described herein are illustrated by way of example and not limited in the accompanying figures in which like reference numerals indicate similar elements and in which:
Aspects of the subject matter described herein are operational with numerous other general purpose or special purpose computing system environments or configurations. Examples of well known computing systems, environments, and/or configurations that may be suitable for use with aspects of the subject matter described herein include, but are not limited to, personal computers, server computers, hand-held or laptop devices, multiprocessor systems, microcontroller-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like.
Aspects of the subject matter described herein may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, and so forth, which perform particular tasks or implement particular abstract data types. Aspects of the subject matter described herein may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices.
With reference to
Computer 110 typically includes a variety of computer-readable media. Computer-readable media can be any available media that can be accessed by the computer 110 and includes both volatile and nonvolatile media, and removable and non-removable media. By way of example, and not limitation, computer-readable media may comprise computer storage media and communication media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by the computer 110. Communication media typically embodies computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of any of the above should also be included within the scope of computer-readable media.
The system memory 130 includes computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM) 131 and random access memory (RAM) 132. A basic input/output system 133 (BIOS), containing the basic routines that help to transfer information between elements within computer 110, such as during start-up, is typically stored in ROM 131. RAM 132 typically contains data and/or program modules that are immediately accessible to and/or presently being operated on by processing unit 120. By way of example, and not limitation,
The computer 110 may also include other removable/non-removable, volatile/nonvolatile computer storage media. By way of example only,
The drives and their associated computer storage media, discussed above and illustrated in
The computer 110 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 180. The remote computer 180 may be a personal computer, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to the computer 110, although only a memory storage device 181 has been illustrated in
When used in a LAN networking environment, the computer 110 is connected to the LAN 171 through a network interface or adapter 170. When used in a WAN networking environment, the computer 110 typically includes a modem 172 or other means for establishing communications over the WAN 173, such as the Internet. The modem 172, which may be internal or external, may be connected to the system bus 121 via the user input interface 160 or other appropriate mechanism. In a networked environment, program modules depicted relative to the computer 110, or portions thereof, may be stored in the remote memory storage device. By way of example, and not limitation,
A baseboard management controller (e.g., BMC 198) may be embedded on the computer 110 to allow the computer 110 to communicate with other devices out-of-band (e.g., without using an operating system). The BMC 198 may be able to report temperature, cooling fan speeds, power mode, operating system status, and the like to a console (such as console 205 of
A data center may include many servers and electronic devices as shown in
In one embodiment, when there are not enough devices on a rack to exceed the power budget assigned to a rack, each device may run at its maximum power level. If more devices are introduced to the rack or if a lower power budget is assigned, however, the devices may exceed the power budget assigned to the rack if they are allowed to run at maximum power. In this case, in accordance with aspects of the subject matter described herein, server priorities may be used to assign power levels to each of the devices in the rack so as to not exceed the power budget assigned to the rack. These aspects as described herein may also be applied to any arbitrary set of devices from as few as one device up to and including all the devices in the data center.
The devices 215-225 may include servers (e.g., servers 215-222), network devices (e.g., network device 223), blade servers (e.g., blade server 225), and other devices (e.g., other device 225). The rack 210 houses the servers 215-217, the network device 223, and the blade server 225 while the rack 211 houses the servers 218-221 and the other device 225. The server 222 may be free-standing and may be located outside of a rack. An exemplary device that may be used as a server such as one of servers 215-222 is the computer 110 of
The communication channel 230 may include one or more networks that connect the devices 215-225 to the console 205 and to other devices and or networks such as the Internet (not shown). A suitable networking protocol such as the TCP/IP protocol, token ring protocol, or some other network protocol may be used to communicate via the communication channel 230.
The communication channel 231 may comprise a network, point-to-point links (e.g., serial connections), or other communication link that allows communication with the devices 215-225 “out-of-band.” Out-of-band in this sense refers to being able to communicate with the devices without regard to the operating system on the devices 215-225.
In one embodiment, a baseboard management controller (BMC) may be embedded on a device to allow the console 205 to communicate with the device out-of-band. An exemplary BMC (e.g., BMC 198) is described in conjunction with
The console 205 may store these power capabilities and priority data in one or more data structures located on a storage device 235. The storage device 235 may comprise computer-readable media such as the computer-readable media described in conjunction with
In one embodiment, the data structure does not include information regarding how the devices are able to implement a power level. For example, the data structure may not include what components a device powers on or off or places in an increased or reduced power state to achieve a power level. Instead, the data structure may simply include the power levels at which the device is capable of operating. In other words, the details of which components are running in which power modes on a particular server may be transparent to a console using the data structure.
In this embodiment, omitting power information about components of each device provides flexibility to describe new power levels that may be introduced in the future. For example, a data structure that was structured to obtain power information about a pre-determined set of hardware may not work properly if new hardware is developed. In addition, having the device determine which components to place in a different power state based on a console commanded power level allows device manufacturers to cause their devices to operate within certain tested configurations.
Using the data structure, the power management software on the console 205 (or on any other machine capable of accessing the storage device 235) may accurately determine how much power is needed by a set of devices and how much power from a budget is remaining for a set of devices. Where location information is included, the power management software may determine whether additional devices may be added to a set of devices (e.g., on a rack) and still consume less power than the power budget allocated to the set of devices.
A device may be instructed to operate at a supported power level by sending a command to the device to operate at the power level. In one embodiment, if the device is under control of an operating system, this may be done through the communication channel 230 by communicating with the operating system (or software executing thereon). In another embodiment, this may be done out-of-band via the communication channel 231 regardless of whether the device is under control of an operating system. When the device receives the command, it determines which components to power on or off or to reduce or increase in power consumption to meet the power level specified by the command. For example, when operating above its minimum power consumption, a CPU may be instructed to decrease its power consumption.
In one embodiment, data may be stored that indicates the power profile that is active on each of the devices. This data may then be used for budgeting power or otherwise without re-querying the devices to obtain the power profiles.
In one embodiment, the power profile field 310 may be omitted from the power capabilities data structure 300. In this embodiment, a device may be instructed to operate at a power no greater than a particular power level by sending the power level to the device.
In one embodiment, having a device “operate at” a particular power level does not mean that the device is required to use the power of the particular power level. Rather, it means that the device may use any power that does not exceed the particular power level. For example, if the work a device is doing is reduced, the device may determine to draw less power until more work is given to the device.
The power capabilities data structure 300 includes an entry for each power level of each device for which power budgeting is desired. In another embodiment, another field may be added to the power capabilities data structure 300 that includes a location (e.g., rack number, physical location as indicated, for example, by coordinates, etc.) or grouping of devices that are affected by a common power budget. This field may be used in conjunction with a power budget data structure 320 to allocate power to each device in the group.
Workloads may be associated with servers in many different ways. For example, when a workload corresponds to all the processes that execute on a single server, the workload ID field 405 may simply include the server ID. As another example, a data structure that explicitly maps workloads to servers may be employed to associate workloads to servers. Other mechanisms may also be used without departing from the spirit or scope of aspects of the subject matter described herein.
A value in the workload ID field 405 serves to identify a workload associated with the priority included in the priority field 410. In one embodiment, a workload corresponds to the processes that execute on a single server. In one embodiment, the single server is a physical server. In another embodiment, the single server is a virtual server. In virtual server embodiments, a workload may correspond to all the processes that execute in the virtual server environment for a single virtual server or the workload may correspond to all the processes that execute on a physical machine (which may include more than one virtual server). In embodiments where a physical machine hosts multiple virtual servers and each virtual server is assigned a priority or where a physical machine is assigned several workloads that are each assigned a priority, the priorities may be combined in some fashion to generate a priority that applies to the physical machine.
If a workload is migrated from one machine to another, the workload ID may still be used to identify the workload and associate a priority with it.
In another embodiment, a workload ID corresponds to a physical server ID. In this embodiment, the workload ID identifies the physical server (and may be thought of as a server ID). If a workload is moved to another physical server, the priority associated with the other physical server may be changed to correspond to the priority of the moving workload.
A workload may also be thought of as a server role. For example, a server may be considered an e-mail server, a web server, a database server, a financial server, a file server, a network server, a print server, a directory server, and the like. As such, a server role may be associated with a priority such that each server fulfilling the server role is assigned the priority.
A priority may be assigned to a workload through various mechanisms. In one embodiment, a workload may be assigned a priority through input received from a user interface. This may be done during deployment, for example. In another embodiment, a workload may be assigned a priority through a manifest that accompanies that workload. A manifest may include the hardware and software needed for a workload as well as the priority. In yet another embodiment, a workload may be assigned a priority via a script or some automated process.
The priority field 410 includes relative power priorities for the identified workloads. In one embodiment, a priority with a lower number has a higher priority than a priority with a higher number. In another embodiment, this may be reversed.
Some workloads are critical to a company's success. Slowing these workloads (e.g., by reducing power to the servers tasked with the workloads) may dramatically decrease a company's profitability or viability. Such workloads may need all the performance capability of the servers upon which they execute. Such workloads may be assigned a high priority. This is represented by the description “Mission Critical” in a description field. Other priorities may have different descriptions associated with them such as “Business Critical,” “Business Priority,” “Low Priority,” and so forth. Indeed, more, fewer, and/or different descriptions may be associated with priorities without departing from the spirit or scope of aspects of the subject matter described herein. Furthermore, as mentioned previously, descriptions of priorities may be entirely omitted without departing from the spirit or scope of aspects of the subject matter described herein.
Descriptions may be used to help a system administrator assign priorities to workloads. For example, a user interface may display the descriptions and allow the system administrator to select one of the descriptions from a drop down text box. Selecting one of the descriptions may cause the priority associated with the description to be assigned to the workload.
In one embodiment, the priority values corresponding to different power profiles are not sequential. This may be done to allow additional priorities to be inserted between two currently existing priorities without renumbering all existing priorities.
The performance desired field 420 may indicate a desired performance of the server upon which the workload is placed. In one embodiment, the performance desired field 420 corresponds to the closest power capability of the server that consumes a percentage at or above the performance desired percentage. For example, if the performance desired is 70% and a server has power capabilities of 1 kilowatt, 800 watts, 600 watts, and 500 watts, the 800 watt performance capability would correspond to the performance desired. In another embodiment, if performance is quantified in other terms (e.g., CPU speed, disk throughput, networking capacity, main memory, etc.), the power capability that provides the desired performance corresponds to the performance desired.
In one embodiment, a data structure such as the priorities/profile data structure 430 may be used to associate priorities with power profiles. The priorities/profile data structure 430 may be used instead of a performance desired field 420 to explicitly associate priorities with power profiles. A priority that is not found in the priorities/profile data structure 430 may be associated with a power profile of the priority that is just higher or just lower than the priority. For example, if a workload has a priority of 25, the priority may be associated with the PP1 or the PP2 profile.
In one embodiment, a power budget may be applied to a collection of devices based on their priorities (or the priorities of the workloads assigned to the devices) without using the performance desired field 420 or an explicit association such as shown in the priorities/profile data structure 430. In this embodiment, the budgeted power is allotted to the various devices based on their relative priority. If there is not enough power for all of the devices to run at maximum power, the power levels for each device is determined using its priority level relative to other devices.
The titles of each field and the title of the data structure described herein are optional and need not be stored in the data structure or elsewhere.
At block 510, a power budget for a set of workloads is obtained. The workloads may be performed by a set of devices. In one embodiment, there is a one to one correspondence between workloads and devices. In another embodiment, more than one workload may execute on a device. For example, referring to
At block 515, a determination is made as to whether the power budget is sufficient for the devices that perform the workloads to run at full power. If so, the actions continue at block 540; otherwise, the actions continue at block 520. For example, referring to
At block 520, a priority for at least one of the workloads is obtained. For example, referring to
At block 525, a power profile of a device assigned to the workload is selected or determined. If a device that is assigned to the workload is operating at a higher power level than associated with the priority of the workload, the power profile associated with the priority of the workload may be selected.
At block 530, the device is instructed to operate at a power level associated with the power profile. For example, referring to
If the power consumed by the devices does not exceed the power budget, the actions continue at block 535; otherwise, the actions may continue at block 520 to set the power level of another of the devices.
If the power budget is exceeded even after reducing all devices to the power levels associated with their workloads, many different actions may occur without departing from the spirit or scope of aspects of the subject matter described herein. For example, a warning may be displayed or sent to a system administrator indicating that the power budget has or may be exceeded by the devices.
As another example, further power savings may occur by reducing the power levels of the devices even further, if possible. This may occur in many different ways. For example, each of the devices (starting with lowest priorities) may be reduced a power level (if possible) until the power budget is not exceeded or until all devices are set to operate at their lowest power level.
If the power that may be consumed by the devices still exceeds the power budget, some of the devices may be powered down. Powering down devices may also be done by priorities where lower priority devices are powered down before higher priority devices. Powering down devices may also be done in some other manner.
It will be recognized that system administrators may desire many different actions to occur if a power budget is or may potentially be exceeded. These actions may be defined in a power policy, by computer code, rules, or otherwise, without departing from the spirit or scope of aspects of the subject matter described herein.
At block 545, power is budgeted to the devices according to the power policy that applies.
At block 550, the devices are allowed to operate at full power.
At block 535, the actions end.
As can be seen from the foregoing detailed description, aspects have been described related to using priorities to select power usage for multiple devices. While aspects of the subject matter described herein are susceptible to various modifications and alternative constructions, certain illustrated embodiments thereof are shown in the drawings and have been described above in detail. It should be understood, however, that there is no intention to limit aspects of the claimed subject matter to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of various aspects of the subject matter described herein.